[0001] The present invention relates to a new process for the preparation of a new catalyst
as well as the use of said new catalyst in polymerization processes.
[0002] In the field of catalysts great efforts are undertaken to further improve the catalyst
types tailored for specific purposes. For instance in polymerization processes Ziegler-Natta
catalysts are widely used having many advantages. Usually such Ziegler-Natta catalysts
are typically supported on carrier materials, such as porous organic and inorganic
support materials, such as silica, MgCl
2 or porous polymeric materials. However such types of catalysts supported on external
porous support or carrier material have quite often drawbacks, especially, if propylene
copolymers with high comonomer content are to be produced. High comonomer content
is possible to incorporate into the polymer, if the external support material is porous
enough, so that the volume of the monomers to be copolymerized does not exceed the
pore volume, and thus stickiness could be avoided. On the other hand, if the porosity
is low, then undesired stickiness problems in the reactor vessels as well as in the
transfer lines will appear, if higher comonomer content is desired. However, serious
drawbacks in using support material with high porosity in order to get high comonomer
content are that the structure of the catalyst particles, and further polymer particles
becomes very weak, and further the bulk density of the polymer will be very low. The
morphology of the catalyst particles is highly dependent on the morphology of the
carrier or support material, and further, due to the replica effect, the morphology
of polymer particles is dependent of the catalyst particles. Weak catalyst and polymer
particle structure will lead easily to break up of particles and thus formation of
hot catalyst particles as well as fines. This will result in fouling and formation
of sticky material, as is well known in the art. In addition low bulk density is detrimental
in view of high output rates, i.e. the polymerization process becomes very uneconomical
to run. In
WO 2005/113613 it is suggested to use a catalyst as described in
WO 03/000757 in the manufacture of heterophasic propylene copolymers. The employed catalyst enables
to increase the output rate since the bulk density of the polymerized product can
be increased. The catalyst is in particular featured by a rather low surface area.
However such types of catalysts are unsuitable in processes in which high amounts
of comonomers shall be incorporated into the polymer. In particular the above mentioned
stickiness cannot be satisfactorily reduced.
[0003] WO 2007/077027 provides also catalyst particles with rather low surface area however additionally
featured by inclusions, i.e. areas within the particles without any catalytic activity.
Such types of catalyst are an advancement compared to the catalysts known in the art
and as described in
WO 03/000757. For instance such types of catalysts enable to produce propylene polymers with a
certain amount of comonomers. However neither this important fact has been recognized
nor has been recognized that a further improvement of such type of catalysts might
bring the breakthrough in the manufacture of propylene copolymers with high comonomer
content.
[0004] Accordingly the object of the present invention is to provide a process for the preparation
of a catalyst which enables to produce propylene copolymers, in particular hetereophasic
propylene copolymers or random propylene copolymers, with high comonomer content,
i.e. even higher than 35 wt.-%, overcoming the known stickiness problems in the reactor
vessels as well as in the transfer lines, and still having a high bulk density. I.e.
according to the invention it is possible to achieve a desired balance between high
comonomer content and high bulk density. Thus it is a further object of the present
invention that the process leads to a catalyst which reduces the risk of reactor fouling.
Moreover a high throughput should be assured due to the high bulk density. Additionally
the process shall assure that the obtained catalyst has a high polymerization activity.
[0005] The finding of the present invention is to produce a catalyst as a solid particle
with low surface area, is compact in nature, i.e. has low porosity, and is of reasonable
to small particle size but of broad particle size distribution, and wherein said particle
comprises solid material with a surface area below 500 m
2/g.
[0006] Accordingly the present invention is directed to a process for the preparation of
a catalyst in form of a solid particle. In principle said catalyst can be obtained
in two different ways. In the first way the preparation of the catalyst in form of
(a) solid particle(s) comprises the steps of
- (a1) preparing a solution (A) of a complex (C) of a metal which is selected from one
of
the groups 1 to 3 of the periodic table (IUPAC) and an electron donor (E) by reacting
a compound (CM) of said metal with said electron donor (E) or a precursor (EP) thereof
in an organic liquid reaction medium (OL1);
- (b1) adding to said solution solid material (SM) obtaining a suspension (S1), said
solid
material (SM)
- (i) does not comprise catalytically active sites,
- (ii) optionally is inert towards the catalyst components,
- (iii) has a specific surface area below 500 m2/g, and
- (iv) has a mean particle size below 100 nm;
- (c1) combining said suspension (S1) at a temperature of at least 50 °C, preferably
in the
temperature range of 50 to 110 °C, like 70 to 100 °C, most preferably in the range
of 85 to 95 °C, with at least one transition metal compound (CT), preferably with
at least one transition metal compound (CT) being in a liquid form at said temperature,
resulting in a precipitation of said catalyst being in the form of a solid particle,
wherein said transition metal compound (CT) is selected from one of the groups 4 to
10 of the periodic table (IUPAC) or a compound of actinide or lanthanide; and
- (d1) optionally separating said catalyst;
said catalyst being in the form of (a) solid particle(s), which
- (i) has (have) a specific surface area of less than 20 m2/g,
- (ii) contain(s) said solid material (SM), and
- (iii) optionally has (have) a particle size distribution of a SPAN value of at least
2.0, more preferably of at least 3.0, yet more preferably of at least 4.0.
[0007] It is especially appreciated that after having combined the suspension (S1) with
at least one transition metal compound (CT) the whole reaction mixture is kept at
least at 50 °C, more preferably is kept in the temperature range of 50 to 110 °C,
like 70 to 100 °C, most preferably in the range of 85 to 95 °C, to secure full precipitation
of the catalyst in form of a solid particle.
[0008] The transition metal compound (CT) in step (c1) is possible to dissolve in an organic
liquid reaction medium (OL2), whereby solution B is formed. In addition it is possible,
but not necessary to add some precipitating agent into the system. Such precipitating
agents are able to effect morphology of the particles formed during the precipitation
step. In a specific process no precipitating agent has been used. A precipitating
agent according to this invention is an agent which promotes the precipitation of
the catalyst in form of a solid particle. The organic liquid medium used as (OL2),
as defined later in this application, can promote the precipitating and thus act and
used as a precipitating agent. However, the final catalyst does not contain any such
medium. In addition, it is possible to use as separate precipitating agent so called
seed material, like silica or MgCl
2 particles, however not to be confused with the solid material (SM) used in the present
invention. However, the particle size of the seed materials might be undesirable big
to some applications, thus the use of such materials has to be considered separately
for different applications.
[0009] Further, a "suspension" throughout the present invention is understood as a homogeneous
fluid containing solid particles. The particles may have sizes that are sufficiently
large for sedimentation. However the suspension caused due to the solid material (SM)
having a very low mean particle size (as non soluble material) may not lead to sedimentation.
Thus the term "suspension" covers also colloids, i.e. homogeneous fluids containing
solid particles, which will not settle over time if left undisturbed. Unlike to a
suspension in a solution the dissolved substance does not exist as a solid. Accordingly
a "solution" according to the present invention is a homogenous mixture composed of
two or more substances. In such a mixture, a solute is dissolved in another substance,
known as a solvent.
[0010] The solid material (SM) of the present invention shall not have any catalytically
active sites, which means nothing other than the solid material (SM) does not comprise,
i.e. does not consist of, components and compounds, like transition metal compounds
of group 4 to 10 of the periodic table (IUPAC), which has catalytic activity in polymerization
processes. Thus in a preferred embodiment the solid material (SM) is catalytically
inert in polymerization processes, in particular in polymerization processes for the
preparation of polyolefin, like polypropylene or polyethylene.
[0011] The term "inert" is understood as defined by
IUPAC (IUPAC Compendium of Chemical Terminology 2nd Edition (1997)). Accordingly inert is something in case it is unreactive under specified conditions.
The "specific conditions" in the present applications are the conditions under which
the catalyst is prepared and conditions under which the polymerization of monomers
as defined is carried out. Accordingly the solid material (SM) is inert preferably
in a temperature range of -50 to 200 °C, more preferably of -20 to 150 °C, at a pressure
from 1 to 100 bar, more preferably from 45 to 100 bar, yet more preferably from 50
to 90 bar, still yet more preferably from 55 to 70 bar.
[0012] Accordingly the term "unreactive" or "inert" indicates that the solid material (SM)
fails to react with the components present during the polymerization process of the
monomers, preferably during the preparation of polyolefin, like polypropylene or polyethylene.
Further the solid material (SM) shall be not only inert toward the monomers or polymers,
but also inert, i.e. unreactive, toward the other components of the catalyst. Thus
the solid material (SM) fails to react with the components used for the preparation
of the catalyst in the form of a solid particle. The solid material (SM) also fails
to react with the final components of the catalyst in the form of a solid particle.
Accordingly the solid material should not contain any organic or inorganic reactive
residues or functional groups. Typical examples of such groups are e.g. -OH, -OR,
-COOH, -COOR, -CONH
2 groups or the like.
[0013] In a second way the preparation of the catalyst in form of (a) solid particle(s)
comprises the steps of
- (a2) preparing a solution (A) of a complex (C) of a metal which is selected from one
of
the groups 1 to 3 of the periodic table (IUPAC) and an electron donor (E) by reacting
a compound (CM) of said metal with said electron donor (E) or a precursor (EP) thereof
in an organic liquid reaction medium (OL1);
- (b2) adding solid material (SM) to at least one transition metal compound (CT),
preferably to at least one transition metal compound (CT) being in a liquid form at
a temperature of at least 50 °C, like in a temperature range of 85 to 95 °C, said
transition metal compound (CT) is selected from one of the groups 4 to 10 of the periodic
table (IUPAC) or a compound of actinide or lanthanide, obtaining a suspension (S2),
said solid material (SM)
- (i) does not comprise catalytically active sites,
- (ii) optionally is inert towards the catalyst components,
- (iii) has a specific surface area below 500 m2/g, and
- (iv) has a mean particle size below 100 nm;
- (c2) combining said solution (A) with said suspension (S2) at a temperature of at
least
50 °C, preferably in the temperature range of 50 to 110 °C, like 70 to 100 °C, most
preferably in the range of 85 to 95 °C resulting in a precipitation of said catalyst
being in the form of solid particles; and
- (d2) optionally separating said catalyst;
said catalyst being in the form of (a) solid particle(s), which
- (i) has (have) a specific surface area of less than 20 m2/g,
- (ii) contain(s) said solid material (SM), and
- (iii) optionally has (have) a particle size distribution of a SPAN value of at least
2.0, more preferably of at least 3.0, yet more preferably of at least 4.0.
[0014] Alternatively the chronology of the steps (a2) and (b2) can be changed or can be
done at the same time.
[0015] The transition metal compound (CT) in step (b2) is possible to dissolve in an organic
liquid reaction medium (OL2), whereby solution B is formed. In addition it is possible,
but not necessary to add some precipitating agent into the system. In a specific process
no precipitating agent has been used.
[0016] In the following the obtained catalyst will be defined in more detail. Subsequently
detailed information to the process steps is provided.
[0017] Accordingly the process of the present invention leads to a catalyst in form of (a)
solid particle(s), wherein the solid particle(s)
- (a) has (have) a specific surface area of less than 20 m2/g,
- (b) comprise(s) a transition metal compound which is selected from one of the groups
4
to 10 of the periodic table (IUPAC) or a compound of actinide or lanthanide, preferably
of the groups 4 to 6 of the periodic table (IUPAC),
- (c) comprise(s) a metal compound which is selected from one of the groups 1 to 3 of
the
periodic table (IUPAC), preferably comprises a Group 2 metal compound (IUPAC), like
a Mg compound,
- (d) comprise(s) solid material (SM), wherein said solid material (SM)
- (i) does not comprise catalytically active sites,
- (ii) optionally is inert towards the catalyst components
- (iii) has a specific surface area below 500 m2/g, and
- (iv) has a mean particle size below 100 nm,
- (e) has (have) a particle size in the range of 5 to 200 µm, and
- (f) optionally has (have) a particle size distribution of a SPAN value of at least
2.0,
more preferably of at least 3.0, yet more preferably of at least 4.0.
[0018] Alternatively the catalyst obtained according to the process can be described as
a catalyst being in the form of (a) solid particle(s), wherein said solid particle(s)
- (a) has (have) a surface area measured of less than 20 m2/g,
- (b) optionally has (have) a particle size distribution of a SPAN value of at least
2.0,
more preferably of at least 3.0, yet more preferably of at least 4.0
- (c) comprise(s)
- (i) a transition metal compound which is selected from one of the groups 4 to
10 of the periodic table (IUPAC) or a compound of actinide or lanthanide, preferably
of the groups 4 to 6 of the periodic table (IUPAC),
and
- (ii) a metal compound which is selected from one of the groups 1 to 3 of the
periodic table (IUPAC), preferably a Group 2 metal compound (IUPAC), like a Mg compound,
wherein (at least) the transition metal compound (or the compound of actinide or lanthanide)
(i) with the metal compound (ii) constitutes the active sites of said particle,
and
- (d) comprise(s) a solid material (SM), wherein said solid material (SM)
- (i) does not comprise catalytically active sites,
- (ii) has a specific surface area below 500 m2/g, and
- (iii) optionally is inert towards the catalyst components
- (iv) has a mean particle size below 100 nm.
[0019] It can be also said, that the catalyst being in a form of (a) solid particle(s) obtained
by the inventive process comprises a solid material (SM) being free from transition
metal compounds which are selected from one of the groups 4 to 10 of the periodic
table (IUPAC) and free from compounds of actinide or lanthanide.
[0020] In a preferred embodiment the solid material (SM) is also inert towards the catalyst
components and components used during the catalyst preparation.
[0021] With the inventive process can be in particular a catalyst produced which has been
not described earlier. Such catalyst is a precipitated solid particle with solid material
(SM) as described above embedded therein. In a specific embodiment such a catalyst
is free of any (detectable) precipitating agent residues.
[0022] Accordingly the present invention is also directed to a catalyst, which is preferably
obtainable by a process as defined in the instant invention, wherein the catalyst
is in form of (a) solid particle(s), said particle(s)
- (a) has (have) a specific surface area of less than 20 m2/g,
- (b) is (are) free of any precipitating agent residues,
- (c) optionally has (have) a particle size distribution of a SPAN value of at least
2.0,
more preferably of at least 3.0, yet more preferably of at least 4.0,
- (d) comprise(s) a transition metal compound which is selected from one of the groups
4
to 10 of the periodic table (IUPAC) or a compound of actinide or lanthanide, preferably
from one of the groups 4 to 6 of the periodic table (IUPAC),
- (e) comprise(s) a metal compound which is selected from one of the groups 1 to 3 of
the
periodic table (IUPAC), preferably a Group 2 metal compound (IUPAC), like a Mg compound,
and
- (f) comprise(s) solid material (SM), wherein said solid material (SM)
- (i) optionally does not comprise catalytically active sites,
- (ii) optionally is inert towards the catalyst components,
- (iii) has a specific surface area below 500 m2/g, and
- (iv) has a mean particle size below 100 nm.
[0023] As stated above the inventive process enables to produce a catalyst being free of
any precipitating agent residues. "Free" in this context throughout the invention
means that not more than 1.0 wt.-%, preferably not more than 0.5 wt.-%, more preferably
not more than 0.05 wt.-%, still more preferably not more than 0.005 wt.-%, yet more
preferably no detectable precipitating agent is present within the solid catalyst.
[0024] Preferably, the catalyst as defined in the previous two paragraphs is a precipitated
solid particle. "Precipitation" according to this invention means that during the
catalyst preparation a chemical reaction in a solution takes place leading to the
desired catalyst insoluble in said solution. Such a precipitated solid catalyst particle
is different in form and shape to a catalyst being also in the form of a solid particle
but obtained by a process wherein first the catalyst has been produced in a solution,
without any precipitation, i.e. the obtained catalyst remains in soluble state. The
solidification of such catalyst is achieved by a subsequent step, said step includes
the change of the solution condition (for instance temperature change, like heating).
[0025] Thus the new catalyst, which is preferably obtainable by a process as defined in
the instant invention, can be alternatively defined as catalyst being in form of (a)
precipitated solid particle(s), wherein said particle(s)
- (a) has (have) a specific surface area of less than 20 m2/g,
- (b) optionally is (are) free of any precipitating agent residue,
- (c) optionally has (have) a particle size distribution of a SPAN value of at least
2.0, more preferably of at least 3.0, yet more preferably of at least 4.0,
- (d) comprise(s) a transition metal compound which is selected from one of the
groups 4 to 10 of the periodic table (IUPAC) or a compound of actinide or lanthanide,
- (e) comprise(s) a metal compound which is selected from one of the groups 1 to
3 of the periodic table (IUPAC), preferably a Group 2 metal compound (IUPAC), like
a Mg compound,
- (f) comprise(s) solid material (SM), wherein the solid material (SM)
- (i) optionally does not comprise catalytically active sites,
- (ii) optionally is inert towards the catalyst components,
- (iii) has a specific surface area below 500 m2/g, and
- (iv) has a mean particle size below 100 nm.
[0026] Preferably the solid material (SM) does not comprise any catalytically active sites
and is inert towards the catalyst components.
[0027] Surprisingly it has been found out that with the above defined catalyst propylene
copolymers with high comonomer content are obtainable without causing any stickiness
problems during the manufacture. Also the throughput of the produced material is high
due to the increased bulk density of the produced polymers. With the new catalyst
heterophasic propylene copolymers are producible with xylene solubles of at least
30 wt.-%, preferably of at least 35 wt.-%, i.e. from at least 30 to 60 wt.-%, like
35 to 45 wt.-%, and nevertheless showing excellent flowability properties. The catalyst
particle is in particular featured by very low surface area which indicates that the
surface of the catalyst particle is essentially free of pores penetrating from the
interior of the particles up to the surface of the particle. On the other hand, the
catalyst particle comprises solid material (SM) which however causes areas within
the particle without any catalytic activity. Because of the "replication effect",
with the new catalyst inter alia a heterophasic propylene copolymer is producible,
wherein said copolymer is featured by a polymer matrix having an internal pore structure,
which however does not extend to the matrix surface. In other words the matrix of
such a heterophasic propylene copolymer has internal pores or cavities which have
no connection to the surface of the matrix. These internal pores or cavities are able
to accumulate the elastomeric propylene copolymer produced in a polymerization stage,
where heterophasic polymer is produced. In a multistage polymerization process this
is usually the second stage. Thus the elastomeric material (which is also called rubber
material) mainly concentrates in the interior of the matrix. The elastomeric material
however is the main causer of the stickiness problems in such type of processes, where
normal supported catalysts are used, which problem can now be avoided, even if high
amounts of elastomeric material is used. In a special and preferred embodiment the
solid material (SM) is evenly distributed within in the solid particle and due to
the replication effect it is also possible to distribute within the propylene polymer
matrix the elastomeric propylene copolymer very evenly. This allows avoiding the formation
of a concentration gradient within the polymer particle. Thus the new catalyst is
the ideal candidate for processes for producing heterophasic propylene copolymers.
But not only for the manufacture of heterophasic systems the outstanding character
of the new catalyst comes obvious also when this new catalyst is employed in processes
for the manufacture of random propylene copolymers with high comonomer content. The
new catalyst enables to produce random propylene copolymers with reasonable high amounts
of comonomer and having good randomness. Moreover also during the process no stickiness
problems occur, even with high comonomer content.
[0028] Naturally the catalyst of the present invention can be used for producing random
and heterophasic polypropylene with lower amounts of comonomer, or for producing homopolymers,
too.
[0029] As stated above one requirement is that the catalyst is in the form of a solid particle.
The particle shape due to the applied process differ in their form compared to the
catalyst particle described for instance in
WO 03/000754,
WO 03/000757 or
WO04/029112. In said documents the catalyst particles are described as having typically clearly
spherical shape, whereas the catalyst particles of the present invention are not necessary
clearly of spherical shape.
[0030] Further the catalyst particle is essentially free of pores or cavities having access
to the surface. In other words the catalyst particle has areas within the particle
being not catalytic active but the catalyst particle is essentially free of pores
or cavities, being open to the surface. The low surface area of the catalyst particle
shows the absence of open pores.
[0031] Conventional Ziegler-Natta catalysts are supported on external support material.
Such material has a high porosity and high surface area meaning that its pores or
cavities are open to its surface. Such kind of supported catalyst may have a high
activity, however a drawback of such type of catalysts is that it tends to produce
sticky material in particular when high amounts of comonomer is used in the polymerization
process.
[0032] On the other hand catalysts as described for instance in
WO 03/000754,
WO 03/000757 or
WO 04/029112 having a compact structure without any internal areas without any catalytic activity,
spherical shape, narrow particle size distribution, and low surface area, tend to
cause stickiness problems, if polypropylene with higher amounts of elastomeric material,
like ethylene, is prepared.
[0033] Therefore it is appreciated that the catalyst as defined herein avoids the drawbacks
of prior art catalysts but still has a rather low to very low surface area, but is
still being able to produce heterophasic polypropylene even with high amount of ethylene
without stickiness problems. A low surface area is insofar appreciated as therewith
the bulk density of the produced polymer can be increased enabling a high throughput
of material. Moreover a low surface area also reduces the risk that the solid catalyst
particle has pores extending from the interior of the particle to the surface. Typically
the catalyst particle has a surface area measured according to the commonly known
BET method with N
2 gas as analysis adsorptive of less than 20 m
2/g, more preferably of less than 15 m
2/g, yet more preferably of less than 10 m
2/g. In some embodiments, the solid catalyst particle in accordance with the present
invention shows a surface area of 5 m
2/g or less, which is the lowest detection limit with the methods used in the present
invention.
[0034] The catalyst particle can be additionally defined by the pore volume. Thus it is
appreciated that the catalyst particle has a porosity of less than 1.0 ml/g, more
preferably of less than 0.5 ml/g, still more preferably of less than 0.3 ml/g and
even less than 0.2 ml/g. In another preferred embodiment the porosity is not detectable
when determined with the method applied as defined in the example section.
[0035] As stated above the solid catalyst particle obtained by the process of the present
invention has a rather broad particle size distribution compared to the catalyst particles
prepared according to the principles described in e.g.
WO 03/000754,
WO 03/000757 or
WO 04/029112. Actually the solid catalyst particles obtained by the processes disclosed in said
publications have a particle size distribution of a SPAN value of clearly below 1.5.
On the other hand the catalyst in the form of a solid particle according to the present
invention has preferably a particle size distribution of a SPAN value of at least
2.0, more preferably of at least 3.0, yet more preferably of at least 4.0. The exact
definition of the SPAN value is given in the example section.
[0036] Moreover the solid catalyst particle in accordance with the present invention typically
has a mean particle size of not more than 500 µm, i.e. preferably in the range of
2 to 500 µm, more preferably 5 to 200 µm. It is in particular preferred that the mean
particle size is below 80 µm, still more preferably below 70 µm. A preferred range
for the mean particle size is 5 to 80 µm, more preferred 10 to 60 µm.
[0037] The inventive catalyst particle comprises of course one or more catalytic active
components. These catalytic active components constitute the catalytically active
sites of the catalyst particle. As explained in detail below the catalytic active
components, i.e. the catalytically active sites, are distributed within the part of
the catalyst particles not being the solid material (SM). Preferably they are distributed
evenly.
[0038] Active components according to this invention are, in addition to the transition
metal compound which is selected from one of the groups 4 to 10 of the periodic table
(IUPAC) or a compound of actinide or lanthanide and the metal compound which is selected
from one of the groups 1 to 3 of the periodic table (IUPAC) (see above and below),
also aluminum compounds, additional transition metal compounds, and/or any reaction
product(s) of a transition compound(s) with group 1 to 3 metal compounds and aluminum
compounds. Thus the catalyst may be formed in situ from the catalyst components by
a precipitation process.
[0039] It should also be understood that the catalyst particle prepared according to the
invention may be used in a polymerization process together with cocatalysts to form
an active catalyst system, which further may comprise e.g. external donors etc.. Furthermore,
said catalyst of the invention may be part of a further catalyst system. These alternatives
are within the knowledge of a skilled person.
[0040] Thus preferably the (precipitated) catalyst particles have a surface area of less
than 20 m
2/g, optionally have a particle size distribution of a SPAN value of at least 2.0,
more preferably of at least 3.0, yet more preferably of at least 4.0, being optionally
free of any precipitating agent, and comprise,
- (a) a transition metal compound which is selected from one of the groups 4 to 10,
preferably titanium, of the periodic table (IUPAC) or a compound of an actinide or
lanthanide,
- (b) a metal compound which is selected from one of the groups 1 to 3 of the periodic
table (IUPAC), preferably a Group 2 metal compound (IUPAC), like a Mg compound,
- (c) optionally an electron donor compound,
- (d) optionally an aluminum compound, and
- (e) solid material (SM), wherein the solid material (SM)
- (i) optionally does not comprise catalytically active sites,
- (ii) optionally is inert towards the catalyst components,
- (iii) has a specific surface area below 430 m2/g, and
- (iv) has a mean particle size below 100 nm.
[0041] Suitable transition metal compounds are in particular transition metal compounds
of transition metals of groups 4 to 6, in particular of group 4, of the periodic table
(IUPAC). Suitable examples include Ti, Fe, Co, Ni, Pt, and/or Pd, but also Cr, Zr,
Ta, and Th, in particular preferred is Ti, like TiCl
4. Of the metal compounds of groups 1 to 3 of the periodic table (IUPAC) preferred
are compounds of group 2 elements, in particular Mg compounds, such as Mg halides,
Mg alkoxides etc. as known to the skilled person.
[0042] As the electron donor compound any donors known in the art can be used, however,
the donor is preferably a mono- or diester of an aromatic carboxylic acid or diacid,
the latter being able to form a chelate-like structured complex. Said aromatic carboxylic
acid ester or diester can be formed in situ by reaction of an aromatic carboxylic
acid chloride or diacid dichloride with a C2-C16 alkanol and/or diol, and is preferable
dioctyl phthalate or di-2-ethyl-hexyl phthalate.
[0043] The aluminum compound is preferably a compound having the formula (I)
AlR
3-nX
n (I)
wherein
- R
- stands for a straight chain or branched alkyl or alkoxy group having 1 to 20, preferably
1 to 10 and more preferably 1 to 6 carbon atoms,
- X
- stands for halogen, preferably chlorine, bromine or iodine, especially chlorine and
- n
- stands for 0,1, 2 or 3, preferably 0 or 1.
[0044] Preferably alkyl groups having from 1 to 6 carbon atoms and being straight chain
alkyl groups, such as methyl, ethyl, propyl, butyl, pentyl or hexyl, preferably methyl,
ethyl, propyl and/or butyl are used.
[0045] Illustrative examples of aluminum compounds to be employed in accordance with the
present invention are diethyl aluminum ethoxide, ethyl aluminum diethoxide, diethyl
aluminum methoxide, diethyl aluminum propoxide, diethyl aluminum butoxide, dichloro
aluminum ethoxide, chloro aluminum diethoxide, dimethyl aluminum ethoxide.
[0046] Other suitable examples for the above defined aluminum compounds are tri-(C1-C6)-alkyl
aluminum compounds, like triethyl aluminum, tri iso-butyl aluminum, or an alkyl aluminum
compound bearing one to three halogen atoms, like chlorine. In particular preferred
is triethylaluminum, diethylaluminum chloride and diethyl aluminum ethoxide.
[0047] As mentioned above catalyst systems may include in addition to the solid catalyst
particles cocatalysts and/ external donor(s) in a manner known in the art.
[0048] As the conventional cocatalyst, e.g. those based on compounds of group 13 of the
periodic 10 table (IUPAC), e.g. organo aluminum, such as aluminum compounds, like
aluminum alkyl, aluminum halide or aluminum alkyl halide compounds (e.g. triethylaluminum)
compounds, can be mentioned. Additionally one or more external donors can be used
which may be typically selected e.g. from silanes or any other well known external
donors in the field. External donors are known in the art and are used as stereoregulating
agent in propylene polymerization. The external donors are preferably selected from
hydrocarbyloxy silane compounds and hydrocarbyloxy alkane compounds.
[0049] Typical hydrocarbyloxy silane compounds have the formula (II)
R'
OSi(OR")
4-O (II)
wherein
- R'
- is an a- or b-branched C3-C12-hydrocarbyl,
- R"
- a C1-C12-hydrocarbyl, and
- O
- is an integer 1-3.
[0050] More specific examples of the hydrocarbyloxy silane compounds which are useful as
external electron donors in the invention are diphenyldimethoxy silane, dicyclopentyldimethoxy
silane, dicyclopentyldiethoxy silane, cyclopentylmethyldimethoxy silane, cyclopentylmethyldiethoxy
silane, dicyclohexyldimethoxy silane, dicyclohexyldiethoxy silane, cyclohexylmethyldimethoxy
silane, cyclohexylmethyldiethoxy silane, methylphenyldimethoxy silane, diphenyldiethoxy
silane, cyclopentyltrimethoxy silane, phenyltrimethoxy silane, cyclopentyltriethoxy
silane, phenyltriethoxy silane. Most preferably, the alkoxy silane compound having
the formula (II) is dicyclopentyl dimethoxy silane or cyclohexylmethyl dimethoxy silane.
[0051] It is also possible to include other catalyst component(s) than said catalyst components
to the catalyst of the invention.
[0052] The scatalyst in the form of (a) solid particle(s) as defined in the instant invention
is furthermore preferably
characterized in that it comprises the catalytically active sites distributed throughout the solid catalyst
particle, however not in those parts comprising solid material (SM) as defined above
and in further detail below. In accordance with the present invention, this definition
means that the catalytically active sites are distributed throughout the catalyst
particle, preferably that the catalytically active sites make up a substantial portion
of the solid catalyst particle in accordance with the present invention. In accordance
with embodiments of the present invention, this definition means that the catalytically
active components, i.e. the catalyst components, make up the major part of the catalyst
particle.
[0053] A further requirement of the present invention is that the solid catalyst particle
comprises solid material (SM) not comprising catalytically active sites. Alternatively
or additionally the solid material (SM) can be defined as material being free of transition
metals of groups 4 to 6, in particular of group 4, like Ti, of the periodic table
(IUPAC) and being free of a compound of actinide or lanthanide. In other words the
solid material (SM) does not comprise the catalytic active materials as defined under
(c) of claim 8, i.e. do not comprise such compounds or elements, which are used to
establish catalytically active sites. Thus in case the solid catalyst particle comprise
any compounds of one of transition metals of groups 4 to 6, in particular of group
4, like Ti, of the periodic table (IUPAC) or a compound of actinide or lanthanide
these are then not present in the solid material (SM). Further the solid material
according to the present invention shall be not understood as possible impurities
caused for instance during the preparation of said catalyst in the form of solid particles.
[0054] Such a solid material (SM) is preferably (evenly) dispersed within the catalyst particle.
Accordingly the solid catalyst particles can be seen also as a matrix in which the
solid material (SM) is dispersed, i.e. form a dispersed phase within the matrix phase
of the catalyst particle. The matrix is then constituted by the catalytically active
components as defined above, in particular by the transition metal compounds of groups
4 to 10 of the periodic table (IUPAC) (or a compound of actinide or lanthanide) and
the metal compounds of groups 1 to 3 of the periodic table (IUPAC). Of course all
the other catalytic compounds as defined in the instant invention can additionally
constitute to the matrix of the catalyst particle in which the solid material (SM)
is dispersed.
[0055] The solid material (SM) usually constitutes only a minor part of the total mass of
the solid catalyst particle. Accordingly the solid particle comprises up to 30 wt.-%
solid material (SM), more preferably up to 25wt.-%. It is in particular preferred
that the solid catalyst particle comprises the solid material (SM) in the range of
1 to 30 wt.-%, more preferably in the range of 2 to 25 wt.-% and yet more preferably
in the range of 5 to 20 wt.-%.
[0056] The solid material (SM) may be of any desired shape, including spherical as well
as elongated shapes and irregular shapes. The solid material (SM) in accordance with
the present invention may have a plate-like shape or they may be long and narrow,
for example in the shape of a fiber. Preferred solid material (SM) is either spherical
or near spherical. Preferably the solid material (SM) has a spherical or at least
near spherical shape. This kind of material is also easily commercially available.
[0057] Preferred solid material (SM) are inorganic materials as well as organic, in particular
organic polymeric materials, suitable examples being nano-materials, such as silica,
montmorillonite, carbon black, graphite, zeolites, alumina, as well as other inorganic
particles, including glass nano-beads or any combination thereof. Suitable organic
particles, in particular polymeric organic particles, are nano-beads made from polymers
such as polystyrene, or other polymeric materials. In any case, the solid material
(SM) employed of the solid catalyst particle has to be inert towards the catalyst
components during the preparation of the solid catalyst particle as well as during
the subsequent use in polymerization reactions. This means that the solid material
(SM) is not to be interfered in the formation of active centres. One further preferred
essential requirement of the solid material (SM) is that it does not comprise any
compounds which are to be used as catalytically active compounds as defined in the
instant invention.
[0058] Thus, for instance the solid material (SM) used in the present invention cannot be
a magnesium-aluminum-hydroxy-carbonate. This material belongs to a group of minerals
called layered double hydroxide minerals (LDHs), which according to a general definition
are a broad class of inorganic lamellar compounds of basic character with high capacity
for anion intercalation (
Quim. Nova, Vol. 27, No.4, 601-614, 2004). This kind of materials are not suitable to be used in the invention due to the
reactivity of the OH- groups included in the material, i.e. OH groups can react with
the TiCl
4 which is part of the active sites. This kind of reaction is the reason for a decrease
in activity.
[0059] Accordingly it is particular preferred that the solid material (SM) is selected form
spherical particles of nano-scale consisting of SiO
2, polymeric materials and/or Al
2O
3.
[0060] By nano-scale according to this invention is understood that the solid material (SM)
has a mean particle size of below 200 nm, more preferred 100 nm or below. Accordingly
it is preferred that the solid material (SM) has a mean particle size of 10 to 100
nm, more preferably from 20 to 90nm, like 20 to 70 nm.
[0061] It should be noted that it is also an essential feature that the solid material (SM)
has small mean particle size, i.e. below 200 nm, preferably below 100 nm, as indicated
above. Thus, many materials having bigger particle size, e.g. from several hundreds
of nm to µm scale, even if chemically suitable to be used in the present invention,
are not the material to be used in the present invention. Such bigger particle size
materials are used in catalyst preparation e.g. as traditional external support material
as is known in the art. One drawback in using such kind of material in catalyst preparation,
especially in final product point of view, is that this type of material leads easily
to inhomogeneous material and formation of gels, which might be very detrimental in
some end application areas, like in film and fibre production.
[0062] The solid material (SM) of the catalyst particle as defined in the instant invention
have a surface area preferably below 500 m
2/g, more preferably below 450 m
2/g. Some useful nanomaterials can have a surface area even below 100 m
2/g.
[0063] By using solid material (SM) with lower surface area (preferably plus low mean particle
size as stated above) the amount of solid material (SM) within the solid catalyst
particle can be decreased but nevertheless an heterophasic propylene copolymer with
high amounts of rubber can be produced without getting any stickiness problems.
[0064] Considering the above especially preferred the solid material (SM) within the solid
catalyst particle has
- (a) a surface area measured below 450 m2/g, and
- (b) a mean particle size below 90 nm
[0065] Such solid material (SM) is preferably present in the solid catalyst particle in
amounts of 5 to 20 wt.-%.
[0066] Preferably the catalyst particle of the present invention is obtained by a specific
process. According to this process the solid material (SM) is either added to the
solution (A) containing the complex (C) of the metal which is selected from one of
the groups 1 to 3 of the periodic table (IUPAC) or to the transition metal compound
(CT) in liquid form or to the solution (B) containing the transition metal compound
(CT) in organic liquid reaction medium (OL2). Transition metal compound (CT) is selected
from one of the groups 4 to 10 of the periodic table (IUPAC). In any case the process
of the present invention is a precipitation process, i.e. the solid catalyst particles
obtained due to chemical reaction are insoluble in the reaction medium.
[0067] Accordingly in a first preparation process, the process comprises the steps of
- (a1) preparing a solution (A) of a complex (C) of a metal which is selected from one
of
the groups 1 to 3 of the periodic table (IUPAC) and an electron donor (E) by reacting
a compound (CM) of said metal with said electron donor (E) or a precursor (EP) thereof
in an organic liquid reaction medium (OL1);
- (b1) adding to said solution solid material (SM) obtaining a suspension (S1), said
solid
material (SM)
- (i) does not comprise catalytically active sites,
- (ii) optionally is inert towards the catalyst components,
- (iii) has a specific surface area below 500 m2/g, and
- (iv) has a mean particle size below 100 nm;
- (c1) combining said suspension (S1) at a temperature of at least 50 °C, preferably
in the
temperature range of 50 to 110 °C, like 70 to 100 °C, most preferably in the range
of 85 to 95 °C, with at least one transition metal compound (CT), preferably with
at least one transition metal compound (CT) being in a liquid form at said temperature,
resulting in a precipitation of said catalyst being in the form of a solid particle,
wherein said transition metal compound (CT) is selected from one of the groups 4 to
10 of the periodic table (IUPAC) or a compound of actinide or lanthanide; and
- (d1) optionally separating said catalyst;
said catalyst being in the form of (a) solid particle(s), which
- (i) has (have) a specific surface area of less than 20 m2/g,
- (ii) contain(s) said solid material (SM), and
- (iii) optionally has (have) a particle size distribution of a SPAN value of at least
2.0, more preferably of at least 3.0, yet more preferably of at least 4.0.
[0068] Alternatively the transition metal compound (CT) is dissolved in an organic liquid
reaction medium (OL2), and used as solution B.
[0069] Alternatively the process comprises the steps of
- (a2) preparing a solution (A) of a complex (C) of a metal which is selected from one
of
the groups 1 to 3 of the periodic table (IUPAC) and an electron donor (E) by reacting
a compound (CM) of said metal with said electron donor (E) or a precursor (EP) thereof
in an organic liquid reaction medium (OL1);
- (b2) adding solid material (SM) to at least one transition metal compound (CT),
preferably to at least one transition metal compound (CT) being in a liquid form at
a temperature of at least 50 °C, like in a temperature range of 85 to 95 °C, said
transition metal compound (CT) is selected from one of the groups 4 to 10 of the periodic
table (IUPAC) or a compound of actinide or lanthanide, obtaining a suspension (S2),
said solid material (SM)
(iv) does not comprise catalytically active sites,
(v) optionally is inert towards the catalyst components,
(iii) has a specific surface area below 500 m2/g, and
(iv) has a mean particle size below 100 nm;
- (c2) combining said solution (A) with said suspension (S2) at a temperature of at
least
50 °C, preferably in the temperature range of 50 to 110 °C, like 70 to 100 °C, most
preferably in the range of 85 to 95 °C resulting in a precipitation of said catalyst
being in the form of solid particles; and
- (d2) optionally separating said catalyst;
said catalyst being in the form of (a) solid particle(s), which
- (i) has (have) a specific surface area of less than 20 m2/g,
- (ii) contain(s) said solid material (SM), and
- (iii) optionally has (have) a particle size distribution of a SPAN value of at least
2.0, more preferably of at least 3.0, yet more preferably of at least 4.0.
[0070] Alternatively the chronology of the steps (a2) and (b2) can be changed or can be
done at the same time.
[0071] The transition metal compound (CT) in step (b2) is possible to dissolve in an organic
liquid reaction medium (OL2).
[0072] Accordingly different to processes where the catalyst is first produced in a solution
and kept in solution before separation, in the present case the produced solid catalyst
particles are insoluble in the reaction medium and precipitate automatically. Moreover
it is preferred that no precipitating agent has been used in the processes as stated
above.
[0073] As stated above in a first step ((a1) or (a2)) a solution (A) of complex (C) of a
metal which is selected from one of the groups 1 to 3 of the periodic table (IUPAC)
and an electron donor (E) is prepared by reacting a compound (CM) of said metal with
said electron donor (E) or a precursor (EP) thereof in an organic liquid reaction
medium (OL1). The metal compound (CM) used for the preparation of the complex (C)
may be any metal compound (CM) which is selected from one of the groups 1 to 3 of
the periodic table (IUPAC). However it is preferred that the complex (C) is a Group
2 metal complex, even more preferred a magnesium complex. Accordingly it is appreciated
that the metal compound (CM) used in the preparation of said complex (C) is a Group
2 metal compound, like a magnesium compound.
[0074] Thus in step (a1) or (a2) preferably first a metal compound (CM) which is selected
from one of the groups 1 to 3 of the periodic table (IUPAC), preferably from a Group
2 metal compound, like from a magnesium compound, containing preferably an alkoxy
moiety is produced. More preferably the metal compound (CM) to be produced is selected
from the group consisting of a Group 2 metal dialkoxide, like magnesium dialkoxide,
a complex containing a Group 2 metal dihalide, like magnesium dihalide, and an alcohol,
and a complex containing a Group 2 metal dihalide, like magnesium dihalide, and a
Group 2 metal dialkoxide, like magnesium dialkoxide.
[0075] Thus the metal compound (CM) which is selected from one of the groups 1 to 3 of the
periodic table (IUPAC), preferably from the Group 2 metal compound, like from the
magnesium compound, is usually titaniumless.
[0076] Most preferably, the magnesium compound is provided by reacting an alkyl magnesium
compound and/or a magnesium dihalide with an alcohol. Thereby, at least one magnesium
compound precursor, selected from the group consisting of a dialkyl magnesium R
2Mg, an alkyl magnesium alkoxide RMgOR, wherein each R is an identical or a different
C
1 to C
20 alkyl, and a magnesium dihalide MgX
2, wherein X is a halogen, is reacted with at least one alcohol, selected from the
group consisting of monohydric alcohols R'OH and polyhydric alcohols R'(OH)
m, wherein R' is a C
1 to
20 hydrocarbyl group and m is an integer selected from 2, 3 ,4 ,5 and 6, to give said
magnesium compound (CM). R' is the same or different in the formulas R'OH and R'(OH)
m. The R of the dialkyl magnesium is preferably an identical or different C
4 to C
12 alkyl. Typical magnesium alkyls are ethylbutyl magnesium, dibutyl magnesium, dipropyl
magnesium, propylbutyl magnesium, dipentyl magnesium, butylpentyl magnesium, butyloctyl
magnesium and dioctyl magnesium. Typical alkyl-alkoxy magnesium compounds are ethyl
magnesium butoxide, magnesium dibutoxide, butyl magnesium pentoxide, magnesium dipentoxide,
octyl magnesium butoxide and octyl magnesium octoxide. Most preferably, one R is a
butyl group and the other R of R
2Mg is an octyl group, i. e. the dialkyl magnesium compound is butyl octyl magnesium.
[0077] The alcohol used to in the reaction with the magnesium compound precursor as stated
in the previous paragraph is a monohydric alcohol, typically C
1 to C
20 monohydric alcohols, a polyhydric (by definition including dihydric and higher alcohols)
alcohol or a mixture of at least one monohydric alcohol and at least one polyhydric
alcohol. Magnesium enriched complexes can be obtained by replacing a part of the monohydric
alcohol with the polyhydric alcohol. In one embodiment it is preferred to use one
monohydric alcohol only.
[0078] Preferable monohydric alcohols are those of formula R'OH in which R' is a C
2 to C
16 alkyl group, most preferably a C
4 to C
12 alkyl group, like 2-ethyl-1-hexanol.
[0079] Typical polyhydric alcohols are ethylene glycol, propene glycol, trimethylene glycol,
1, 2-butylene glycol, 1, 3-butylene glycol, 1, 4-butylene glycol, 2, 3-butylene glycol,
1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, pinacol, diethylene glycol, triethylene
glycol, glycerol, trimethylol propane and pentaerythritol. Most preferably the polyhydric
alcohol is selected from the group consisting of ethylene glycol, 2-butyl-2-ethyl-1,
3-propanediol and glycerol.
[0080] The reaction conditions used to obtain the metal compound (CM) which is selected
from one of the groups 1 to 3 of the periodic table (IUPAC), preferably the metal
compound (CM) of Group 2, even more preferred the magnesium compound, may vary according
to the used reactants and agents. However according to one embodiment of the present
invention, said magnesium compound precursor is reacted with said at least one alcohol
at temperature of 30 to 80 °C for 10 to 90 min, preferably about 30 min.
[0081] After having obtained the metal compound (CM) which is selected from one of the groups
1 to 3 of the periodic table (IUPAC), preferably the metal compound of Group 2, even
more preferred the magnesium compound, said compound (CM) is further reacted with
a dicarboxylic acid dihalide. Preferably said metal compound reacts with a dicarboxylic
acid dihalide having the formula (X)
wherein
each R" is an identical or different C
1 to C
20 hydrocarbyl group or both R"s form together with the two unsaturated carbons seen
in the formula (X) a C
5 to C
20 aliphatic or aromatic ring, and
X' is a halogen
to give the complex (C) of step (a1) or (a2).
[0082] Among non-cyclic dicarboxylic acid dihalides, the group consisting of maleic acid
dihalide, fumaric acid dihalide and their R" substituted derivatives such as citraconic
acid dihalide and mesaconic acid dihalide, respectively, are the most important.
[0083] Among the cyclic dicarboxylic acid dihalides, the group consisting of phthalic acid
dihalide (1,2-benzene dicarboxylic acid dihalide), its hydrogenate 1, 2-cyclohexane
dicarboxylic acid dihalide, and their derivatives, is the most important. Most preferably,
said dicarboxylic acid dihalide is phthaloyl dichloride.
[0084] Preferably the magnesium compound is reacted with the dicarboxylic acid halide in
a molar ratio Mg
total added/dicarboxylic acid halide of 1 : 1 and 1 : 0.1, preferably between 1 : 0. 6 and 1
: 0. 25.
[0085] Preferably the metal compound (CM) which is selected from one of the groups 1 to
3 of the periodic table (IUPAC), more preferably the metal compound of Group 2, even
more preferably the magnesium compound, is reacted with the dicarboxylic acid dihalide
under at least one of the following conditions :
- adding said dicarboxylic acid dihalide under room temperature and
- heating the obtained reaction mixture to a temperature of 20 to 80 °C, preferably
of 50 to 70 °C
- keeping the temperature for 10 to 90 min, preferably for 25 to 35 min.
[0086] The organic liquid reaction medium (OL1) used for the preparation of the complex
(C) in step (a1) or (a2) can be any organic solvent as long as it is ensured that
the complex (C) is dissolved at ambient temperatures, i.e. at temperatures up to 80
°C (20 to 80 °C). Accordingly it is appreciated that the organic liquid reaction medium
(OL1) comprises, preferably consists of, C
5 to C
10 hydrocarbon, more preferably of a C
6 to C
10 aromatic hydrocarbon, like toluene.
[0087] Subsequently the obtained solution of complex (C) (solution A) is first mixed with
the solid material (SM) to obtain a suspension (S1) and afterwards brought in contact
with at least one compound (CT) of a transition metal (alternative route 1) or the
obtained complex (C) is directly added to a suspension (S2) of at least one transition
metal compound (CT) and the solid material (SM). In both cases, i.e. in the steps
(c1) and (c2), the temperature must be relatively high, i.e. at least 50 °C, preferably
in the temperature range of 50 to 110 °C, more preferably of 70 to 100 °C, like 85
to 915°C, to ensure that the precipitation occurs after the complex (C) is brought
in contact with the transition metal compound (CT). Thus contrary to the applied processes
as for instance disclosed in
WO 03/000754 and
WO 03/000757, in which the catalyst is also obtained by a chemical reaction, but said catalyst
remains in solution after completion of the chemical reaction, in the present process
the conditions are set in a manner that ensure an immediate precipitation of the solid
catalyst particles. Accordingly one important requirement of the present process is
to keep the temperature in step (c1) and (c2) as set out in this paragraph.
[0088] When adding the solution (A) or the suspension (S1) to the at least one transition
metal compound (CT) (steps (c1) and (d2)) mixing is appreciated. Suitable mixing techniques
include the use of mechanical as well as the use of ultrasound for mixing, as known
to the skilled person.
[0089] Further it is appreciated that the organic liquid reaction media (OL1) and (OL2)
are selected in a way which supports the immediate precipitation of the solid catalyst
particle. As stated above, the organic liquid reaction medium (OL1) comprises, preferably
consists of, C
5 to C
10 hydrocarbon, more preferably of a C
6 to C
10 aromatic hydrocarbon, like toluene. The organic liquid reaction medium (OL2), where
TiCl
4 can be solved, can be the same as the organic liquid reaction medium (OL1) or can
be different thereto, the latter being preferred. Preferably the organic liquid reaction
medium (OL2) is C
5 to C
10 hydrocarbon, more preferably of a C
6 to C
10 alkane, like heptanes, octane or nonane, or any mixtures thereof. It is in particular
appreciated that the organic liquid reaction medium (OL1) is C
6 to C
10 aromatic hydrocarbon, like toluene, and the organic liquid reaction medium (OL2)
is a C
6 to C
10 alkane, like heptanes.
[0090] After precipitation the solid catalyst particle is washed in a known manner. Accordingly
it is preferred that solid catalyst particle is washed with toluene, preferably with
hot (e. g. 90 °C) toluene and subsequently with heptane, most preferably with hot
(e. g. 90 C) heptane. Further washings, e.g. with gold heptanes, or pentane are possible
as well.
[0091] Suitable transition metal compounds (CT) are in particular transition metal compounds
(CT) of transition metals of groups 4 to 6, in particular of group 4, of the periodic
table (IUPAC). Suitable examples include Ti, Fe, Co, Ni, Pt, and/or Pd, but also Cr,
Zr, Ta, and Th, in particular preferred is Ti, like TiCl
4.
[0092] One essential aspect of the present process is to incorporate solid material (SM)
in the solid catalyst particles. The solid material (SM) can be added to solution
(A) or to the solution (B) of at least one transition metal compound (CT) and optionally
an organic liquid reaction medium (OL2) obtaining a suspension (S1) and (S2), respectively.
However it is preferred that the solid material (SM) is added to the solution (A)
after the complex (C) has been formed and the thus obtained suspension (S1) is added
to at least one transition metal compound (CT) in liquid form.
[0093] Additional catalyst components, like compounds of group 13 metal, as described above,
can be added at any step before the final recovery of the solid catalyst.
[0094] The invention is further directed to the use of the inventive catalyst in polymerization
processes, in particular in processes in which heterophasic material, like heterophasic
propylene copolymer, or random propylene copolymer is produced.
[0095] Further, the invention is related to a polymerization process for producing propylene
polymers, especially propylene copolymers, and more specifically to heterophasic propylene
copolymers where a catalyst of the present invention is used.
[0096] The process for producing heterophasic polymers comprises at least two stages, in
the first stage the propylene polymer matrix in the presence of the catalyst system
as defined in the instant invention is produced. In the second stage the elastomeric
propylene copolymer is polymerized in the presence of the propylene polymer matrix.
Preferably also in the second stage the catalyst system as defined in the instant
invention is present.
[0097] The process for the manufacture for propylene random copolymer can be a single stage
process using a bulk phase, slurry phase or gas phase reactor. However it is preferred
that the propylene random copolymer is produced in a multistage process in which the
catalyst system of the instant invention is employed.
[0098] Preferably the polymerization conditions for the slurry reactor may be as follows:
- the temperature is within the range of 40 to 110 °C, preferably between 60 and 90
°C,
- the pressure is within the range of 20 to 80 bar, preferably between 30 to 60 bar,
- hydrogen can be added for controlling the molar mass in a manner known per se.
[0099] The polymerization conditions in the gas phase reactor may be as follows:
- the temperature is within the range of 50 and 130 °C, preferably between 65 and 100
°C, and still more preferably between 70 and 85 °C.
- the pressure is within the range of 5 to 50 bar, preferably between 15 to 35 bar,
- hydrogen can be added for controlling the molar mass in a manner known per se.
[0100] The present invention is further described by way of examples.
EXAMPLES
1. Definitions/Measuring Methods
[0101] The following definitions of terms and determination methods apply for the above
general description of the invention as well as to the below examples unless otherwise
defined.
MFR2 (230°C) is measured according to ISO 1133 (230 °C, 2.16 kg load).
RANDOMNESS in the FTIR measurements, films of 250 mm thickness were compression molded at 225
°C and investigated on a Perkin-Elmer System 2000 FTIR instrument. The ethylene peak
area (760-700 cm
-1) was used as a measure of total ethylene content. The absorption band for the structure
-P-E-P- (one ethylene unit between propylene units), occurs at 733 cm
-1. This band characterizes the random ethylene content. For longer ethylene sequences
(more than two units), an absorption band occurs at 720 cm
-1. Generally, a shoulder corresponding to longer ethylene runs is observed for the
random copolymers. The calibration for total ethylene content based on the area and
random ethylene (PEP) content based on peak height at 733 cm
-1 was made by 13C-NMR. (
Thermochimica Acta, 66 (1990) 53-68).
[0102] Melting temperature Tm, crystallization temperature Tc, and the degree of crystallinity:
measured with Mettler TA820 differential scanning calorimetry (DSC) on 5-10 mg samples.
Both crystallization and melting curves were obtained during 10 °C/min cooling and
heating scans between 30 °C and 225 °C. Melting and crystallization temperatures were
taken as the peaks of endotherms and exotherms.
[0103] Ethylene content, in particular of the matrix, is measured with Fourier transform infrared spectroscopy
(FTIR) calibrated with 13C-NMR. When measuring the ethylene content in polypropylene,
a thin film of the sample (thickness about 250 mm) was prepared by hotpressing. The
area of absorption peaks 720 and 733 cm
-1 was measured with Perkin Elmer FTIR 1600 spectrometer. The method was calibrated
by ethylene content data measured by 13C-NMR.
[0104] Xylene soluble fraction (XS) and amorphous fraction (AM)
2.0 g of polymer are dissolved in 250 ml p-xylene at 135 °C under agitation. After
30±2 minutes the solution is allowed to cool for 15 minutes at ambient temperature
and then allowed to settle for 30 minutes at 25±0.5 °C . The solution is filtered
with filter paper into two 100 ml flasks.The solution from the first 100 ml vessel
is evaporated in nitrogen flow and the residue is dried under vacuum at 90 °C until
constant weight is reached.
m
0 = initial polymer amount (g)
m
1 = weight of residue (g)
v
0 = initial volume (ml)
v
1 = volume of analyzed sample (ml)
[0105] The solution from the second 100 ml flask is treated with 200 ml of acetone under
vigorous stirring. The precipitate is filtered and dried in a vacuum-oven at 90 °C.
AM% = (100 x m
2 x v0) / (m
0 x v
1)
m
0 = initial polymer amount (g)
m
2 = weight of precipitate (g)
v
0 = initial volume (ml)
v
1 = volume of analyzed sample (ml)
[0106] Flowability 90 g of polymer powder and 10 ml of xylene was mixed in a closed glass bottle and
shaken by hand for 30 minutes. After that the bottle was left to stand for an additional
1.5 hour while occasionally shaken by hand. Flowability was measured by letting this
sample flow through a funnel at room temperature. The time it takes for the sample
to flow through is a measurement of stickiness. The average of 5 separate determinations
was defined as flowability. The dimensions of the funnel can be deducted from figure
2.
[0107] Porosity: BET with N2 gas, ASTM 4641, apparatus Micromeritics Tristar 3000; sample preparation
(catalyst and polymer): at a temperature of 50 °C, 6 hours in vacuum.
[0108] Surface area: BET with N
2 gas ASTM D 3663, apparatus Micromeritics Tristar 3000: sample preparation (catalyst
and polymer): at a temperature of 50 °C, 6 hours in vacuum.
[0109] Mean particle size is given in nm and measured with Coulter Counter LS200 at room temperature with n-heptane
as medium; particle sizes below 100 nm by transmission electron microscopy.
[0110] Median particle size (d50) is given in nm and measured with Coulter Counter LS200 at room temperature with n-heptane
as medium.
[0111] Particle size (d10) is given in nm and measured with Coulter Counter LS200 at room temperature with n-heptane
as medium.
[0112] Particle size (d90) is is given in nm and measured with Coulter Counter LS200 at room temperature with
n-heptane as medium.
[0113] SPAN is defined as follows:
[0114] Bulk density BD is measured according ASTM D 1895
Determination of Ti and Mg amounts in the catalyst
[0115] The determination of Ti and Mg amounts in the catalysts components is performed using
ICP. 1000 mg/l standard solutions of Ti and Mg are used for diluted standards (diluted
standards are prepared from Ti and Mg standard solutions, distilled water and HNO
3 to contain the same HNO
3 concentration as catalyst sample solutions).
[0116] 50-100 mg of the catalyst component is weighed in a 20 ml vial (accuracy of weighing
0.1 mg). 5 ml of concentrated HNO3 (Suprapur quality) and a few milliliters of distilled
water is added. The resulting solution is diluted with distilled water to the mark
in a 100 ml measuring flask, rinsing the vial carefully. A liquid sample from the
measuring flask is filtered using 0.45 µm filter to the sample feeder of the ICP equipment.
The concentrations of Ti and Mg in the sample solutions are obtained from ICP as mg/l.
[0117] Percentages of the elements in the catalyst components are calculated using the following
equation:
where
A = concentration of the element (mg/l)
V = original sample volume (100 ml)
m = weight of the catalyst sample (mg)
V
a = volume of the diluted standard solution (ml)
V
b = volume of the 1000 mg/l standard solution used in diluted standard solution (ml)
Determination of donor amounts in the catalyst components
[0118] The determination of donor amounts in the catalyst components is performed using
HPLC (UV-detector, RP-8 column, 250 mm × 4 mm). Pure donor compounds are used to prepare
standard solutions.
[0119] 50-100 mg of the catalyst component is weighed in a 20 ml vial (accuracy of weighing
0.1 mg). 10 ml acetonitrile is added and the sample suspension is sonicated for 5-10
min in an ultrasound bath. The acetonitrile suspension is diluted appropriately and
a liquid sample is filtered using 0.45 µm filter to the sample vial of HPLC instrument.
Peak heights are obtained from HPLC.
[0120] The percentage of donor in the catalyst component is calculated using the following
equation:
where
A
1 = height of the sample peak
c = concentration of the standard solution (mg/l)
V = volume of the sample solution (ml)
A
2 = height of the standard peak
m = weight of the sample (mg)
2. Preparation of the Examples:
Example 1: Preparation of a soluble Mg-complex
[0121] A magnesium complex solution was prepared by adding, with stirring, 55.8 kg of a
20 % solution in toluene of BOMAG (Mg(Bu)
1,5(Oct)
0,5) to 19,4 kg 2-ethylhexanol in a 150 1 steel reactor. During the addition the reactor
contents were maintained below 20 °C. The temperature of the reaction mixture was
then raised to 60 °C and held at that level for 30 minutes with stirring, at which
time reaction was complete. 5.50 kg 1,2-phthaloyl dichloride was then added and stirring
of the reaction mixture at 60 °C was continued for another 30 minutes. After cooling
to room temperature a yellow solution was obtained.
[0122] Example 2: Catalyst with solid material
[0123] 19.5 ml titanium tetrachloride and 10 ml n-heptane were placed in a 300 ml glass
reactor equipped with a mechanical stirrer. Mixing speed was adjusted to 170 rpm.
The reactor was heated to 90 °C and a suspension of 0.4 g silica nanoparticles (Nanostructured
& Amorphous Materials Inc., 80 nm, stock #4830HT) in 28.4 g of the Mg-complex was
added to the stirred mixture over a period of 10 minutes. Stirring at 90 °C was then
continued for another 30 minutes.
[0124] After settling and syphoning the solids underwent washing with 100 ml of toluene
at 90 °C for 30 minutes, a mixture of 0.11 ml diethyl aluminum chloride and 100 ml
toluene at 90 °C for 30 minutes, 60 ml heptane at 90 °C for 20 minutes, and 60 ml
heptane at 20 °C for 10 minutes. Finally, the solids were dried at 60 °C by nitrogen
purge, to yield a yellow, air-sensitive powder. Al content in the catalyst was 0.59
wt-%
Example 3 (Comparative): Catalyst without solid material
[0125] Catalyst with low surface area and compact structure was prepared as follows:
24. kg titanium tetrachloride were placed in a 90 1 steel reactor and 21.0 kg of Mg-complex
were then added to the stirred reaction mixture over a period of two hours. During
the addition of the Mg-complex the reactor contents were maintained below 35 °C.
4.5 kg n-heptane and 1.05 1 Viscoplex®1-254 of RohMax Additives GmbH (a polyalkyl methacrylate with a viscosity at 100 °C
of 90 mm2/s and a density at 15 °C of 0.90 g/ml) were then added to the reaction mixture at
room temperature and stirring was maintained at that temperature for a further 60
minutes.
[0126] The temperature of the reaction mixture was then slowly raised to 90°C over a period
of 60 minutes and held at that level for 30 minutes with stirring. After settling
and siphoning the solids underwent washing with a mixture of 0,244 of a 30 % solution
in toluene of diethyl aluminum dichlorid and 50 kg toluene for 110 minutes at 90 °C,
30 kg toluene for 110 minutes at 90 °C, 30 kg n-heptane for 60 minutes at 50 °C, and
30 kg n-heptane for 60 minutes at 25 °C.
[0127] Finally, 4.0 kg white oil (Primol 352; viscosity at 100 °C of 8.5 mm
2/s; density at 15 °C of 0.87 g/ml) was added to the reactor. The obtained oil slurry
was stirred for a further 10 minutes at room temperature before the product was transferred
to a storage container.
Example 4 (Comparative): Catalyst with nanoparticles, different preparation method
[0129] 19.5 ml titanium tetrachloride was placed in a 300 ml glass reactor equipped with
a mechanical stirrer. Mixing speed was adjusted to 170 rpm. 32.0 g of the Mg-complex
were5 then added to the stirred reaction mixture over a 10 minute period. During the
addition of the Mg-complex the reactor contents were maintained below 30 °C.
[0130] 1,0 ml of a solution in toluene of 3.0 mg polydecene and 2,0 mlViscoplexR1-254 of
RohMax Additives GmbH (a polyalkyl methacrylate with a viscosity at 100 °C of 90 mm2/s
and a density at 15 °C of 0.90 g/ml) were then added, and after 5 minutes stirring
at room temperature a suspension of 0.4 g Si02 nanoparticles (mean particle size 80
nm; surface area 440 m2/g; bulk density 0.063 g/cm3) in 10,0 ml of n-heptane was added.
Stirring was maintained at room temperature for 30 minutes.
[0131] The temperature of the reaction mixture was then slowly raised to 90 °C over a period
of 20 minutes and held at that level for 30 minutes with stirring.
[0132] After settling and syphoning the solids underwent washing with a mixture of 0.11
ml diethyl aluminum chloride and 100 ml toluene at 90°C for 30 minutes, 60 ml heptane
for 20 minutes 20 at 90 °C and 60 ml pentane for 10 minutes at 25°C. Finally, the
solids were dried at 60 °C by nitrogen purge, to yield a yellow, air-sensitive powder.
Table 1: Properties of the catalyst particles
|
|
Ex 2 |
Ex 3 comp |
Ex 4 comp |
Ti |
[wt.-%] |
3.76 |
3.81 |
3,9 |
Mg |
[wt.-%] |
12.1 |
11.4 |
12,5 |
Phthalate*P |
[wt.-%] |
25.0 |
24.4 |
26,7 |
Nanoparticles |
[wt.-%] |
9.1 |
- |
8,9 |
Surface area** |
[m2/g] |
< 5.0 |
< 5.0 |
< 5.0 |
Porosity |
[ml/g] |
BL*** |
BL |
BL |
Mean particle size |
[µm] |
42.2 |
20.2 |
25.60 |
D10 |
[µm] |
1.97 |
5,2 |
16,2 |
D50 |
[µm] |
17.68 |
21.9 |
34,5 |
D90 |
[µm] |
104.80 |
28,4 |
55,4 |
SPAN |
|
5.8 |
1,1 |
1,1 |
* The phthalate is bis(2-ethylhexyl)phthalate
** the lowest limit for measure surface area by the used method is 5 m2/g
*** BL means below the detection limit |
Random polymerizations
Example 5
[0133] All raw materials were essentially free from water and air and all material additions
to the reactor and the different steps were done under inert conditions in nitrogen
atmosphere. The water content in propylene was less than 5 ppm.
Stage 1: Bulk polymerisation step
[0134] The polymerisation was done in a 5 litre reactor, which was heated, vacuumed and
purged with nitrogen before taken into use. 138 µl TEA (tri ethyl Aluminium, from
Witco used as received), 47 µl donor D (dicyclo pentyl dimethoxy silane, from Wacker,
dried with molecular sieves) and 30 ml pentane (dried with molecular sieves and purged
with nitrogen) were mixed and allowed to react for 5 minutes. Half of the mixture
was added to the reactor and the other half was mixed with 12.4 mg highly active and
stereo specific Ziegler Natta catalyst of example 2 of the invention. After about
10 minutes was the ZN catalyst/TEA/donor D/pentane mixture added to the reactor. The
Al/Ti molar ratio was 150 and the Al/Do molar ratio was 5. 350 mmol hydrogen and 1400
g were added to the reactor. Ethylene was added continuously during polymerisation
and totally 19.2 g was added. The temperature was increased from room temperature
to 70 °C during 16 minutes. The reaction was stopped, after 30 minutes at 70 °C, by
flashing out unreacted monomer. Finally the polymer powder was taken out from the
reactor and analysed and tested. The polymer details are seen in table 2A.
Stage 2: Gas phase reactor
[0135] After having flashed out unreacted propylene after the bulk polymerisation step the
polymerisation was continued in gas phase. After the bulk phase the reactor was pressurised
up to 5 bar and purged three times with a 0.085 mol/mol ethylene/propylene mixture.
150 mmol hydrogen was added and temperature was increased to 80 °C and pressure with
the aforementioned ethylene/propylene mixture up to 20 bar during 13 minutes. Consumption
of ethylene and propylene was followed from scales. The reaction was allowed to continue
until a total consumption (ethylene + propylene) of about 300 g was reached, which
means half of the final product was produced in the bulk phase polymerisation and
half in the gas phase polymerisation. When opening the reactor it was seen that the
polymer powder was easily free flowing. XS of the polymer was 28 wt.-% and ethylene
content in the product was 6.9 wt.-%, meaning that ethylene content in material produced
in the gas phase was 10,0 wt.-%. Other details are seen in table 2A
Example 6
Stage 1: Bulk polymerisation step
[0136] This first stage reaction was done as described above in example 5, with the exception
that the catalyst of example 3 (comparative) was used. Ethylene content in the polymer
was 3.7 wt.-%. The other details are shown in table 2B.
Stage 2: Gas phase reactor
[0137] The second stage was done as described above in example 5, of course again with the
exception that the catalyst of example 3 (comparative) was used. When opening the
reactor after polymerisation it was seen that about 2/3 of the polymer powder was
loosely glued together. XS of the product was 23 wt.-%. Ethylene content in the final
product was 6.3 wt.-%, which means that the ethylene content in the material produced
in the gas phase was 8.9 wt.-%. The other details are shown in table 2B.
Example 7
Stage 1: Bulk polymerisation step
[0138] This first stage reaction was done as described above in example 5, with the exception
that the catalyst of example 4 (comparative) was used. Ethylene content in the polymer
was 3.7 wt.-%. The other details are shown in table 2B.
Stage 2: Gas phase reactor
[0139] The second stage was done as described above in example 5, of course again with the
exception that the catalyst of example 4 (comparative) was used. When opening the
reactor it was seen that the polymer powder was free flowing. XS of the polymer was
22 wt.-% and ethylene content in the product was 6.0 wt.-%, meaning that ethylene
content in material produced in the gas phase was 8.3 wt.-%. Other details are seen
in table 2B.
Table 2A: Polymerisation and Properties of the random polypropylene
|
|
Ex 5 |
Ex 5 |
|
|
1.stage |
2.stage |
catalyst |
|
Ex 2 |
Ex 2 |
Cat amount |
[mg] |
15 |
15 |
Bulk |
|
|
|
Ethylene fed |
[g] |
19.2 |
19.4 |
Gas phase polymerisation |
|
|
|
Time |
[min] |
- |
162 |
Ethylene/propylene in feed |
[mol/mol] |
- |
0.085 |
Ethylene fed |
[g] |
- |
25 |
Propylene fed |
[g] |
- |
459 |
Yield |
[g] |
311 |
600 |
Split: Bulk/gas phase material |
[weight/weight] |
100/0 |
52/48 |
Polymer |
|
|
|
Ethylene |
[wt.-%] |
4.0 |
6.9 |
Ethylene in gas phase material |
[wt.-%] |
- |
10.0 |
Randomness |
[%] |
74.1 |
64.4 |
XS |
[wt.-%] |
9.3 |
28.1 |
MFR |
[g/10min] |
13.2 |
6.8 |
Flowability |
[seconds] |
- |
3.8 |
Table 2B: Polymerisation and Properties of the random polypropylene, comparative examples
|
|
Ex 6 |
Ex 6 |
Ex 7 |
Ex 7 |
|
|
1.stage |
2.stage |
1.stage |
2.stage |
Catalyst type |
|
Ex 3 |
Ex 3 |
Ex 4 |
Ex 4 |
|
|
|
|
|
|
Cat amount |
[mg] |
16.2 |
16.2 |
12.4 |
12.5 |
Bulk polymerisation |
|
|
|
|
|
Ethylene fed |
[g] |
19.7 |
19.3 |
19.2 |
19.3 |
Gas phase polymerisation |
|
|
|
|
|
Time |
[min] |
- |
77 |
- |
65 |
Ethylene/propylene in feed |
[mol/mol] |
- |
0.085 |
- |
0.085 |
Ethylene fed |
[g] |
- |
26.2 |
- |
25 |
Propylene fed |
[g] |
- |
467 |
- |
434 |
Yield |
[g] |
318 |
630 |
282 |
598 |
Split: Bulk/gas phase |
[weight/weight] |
100/0 |
50/50 |
100/0 |
50/50 |
Polymer |
|
|
|
|
|
Ethylene |
[wt.-%] |
3.7 |
6.3 |
3.7 |
6 |
Ethylene in gas phase |
[wt.-%] |
- |
8.9 |
- |
8.3 |
Randomness |
[%] |
75.7 |
66.9 |
75.6 |
67.7 |
XS |
[wt.-%] |
7.6 |
23.3 |
6.7 |
22 |
MFR |
[g/10min] |
7.5 |
5.8 |
5.0 |
4.0 |
Flowability |
[seconds] |
- |
5.7 |
- |
2.3 |
[0140] As can be seen from the results, the flowability of the polymer is very good in polymers
produced with the catalyst of the invention, in spite of the high ethylene content
and high XS values compared to the ones produced with the prior art catalyst (example
6), and also at least, if not even better compared to the polymers produced with the
catalyst of example 4, which contains as well nanoparticles, but is prepared with
a different method.
Heterophasic polymerisations
Example 8:
[0141] All raw materials were essentially free from water and air and all material additions
to the reactor and the different steps were done under inert conditions in nitrogen
atmosphere. The water content in propylene was less than 5 ppm.
Stage 1: Bulk polymerisation step
[0142] The polymerisation was done in a 5 litre reactor, which was heated, vacuumed and
purged with nitrogen before taken into use. 276 µl TEA (tri ethyl Aluminium, from
Witco used as received), 47 µl donor Do (dicyclo pentyl dimethoxy silane, from Wacker,
dried with molecular sieves) and 30 ml pentane (dried with molecular sieves and purged
with nitrogen) were mixed and allowed to react for 5 minutes. Half of the mixture
was added to the reactor and the other half was mixed with 14.9 mg highly active and
stereo specific Ziegler Natta catalyst of example 2 of the invention. After about
10 minutes was the ZN catalyst/TEA/donor D/pentane mixture added to the reactor. The
Al/Ti molar ratio was 250 and the Al/Do molar ratio was 10. 200 mmol hydrogen and
1400 g were added to the reactor. The temperature was increased from room temperature
to 80 °C during 16 minutes. The reaction was stopped, after 30 minutes at 80 °C, by
flashing out unreacted monomer. Finally the polymer powder was taken out from the
reactor and analysed and tested. The MFR of the product was 13,5. The other polymer
details are seen in table 3A. The result from the flowability test was 2.8 seconds.
Stage 2: Gas phase reactor
[0143] This example was done in accordance with example 9, but after having flashed out
unreacted propylene after the bulk polymerisation step the polymerisation was continued
in gas phase (rubber stage). After the bulk phase the reactor was pressurised up to
5 bar and purged three times with a 0.75 mol/mol ethylene/propylene mixture. 200 mmol
hydrogen was added and temperature was increased to 80 °C and pressure with the aforementioned
ethylene/propylene mixture up to 20 bar during 14 minutes. Consumption of ethylene
and propylene was followed from scales. The reaction was allowed to continue until
in total 356 g of ethylene and propylene had been fed to the reactor. MFR of the final
product was 4,1 and XS was 43,8 wt.-%. The polymer powder showed almost no stickiness,
although a polymerisation time in at the second stage was long (85 min). This can
be also seen as a reasonably good flowability result. The result from the flowability
test was 10,4 seconds. Other details and results are seen in table 3A
Example 9
[0144] After the first stage of example 8 the polymerisation was continued as in example
8 however with a shorter polymerisation time (45 min). Details and results are seen
in table 3A.
Example 10
[0145] The procedure of example 8 was repeated at the first and second stage, however, catalyst
of example 4 (comparative) was used. Other details and results can be seen in table
3B. Other details and results can be seen in table 3B.
Example 11
[0146] The procedure of example 8 was repeated at the first and second stage, however, catalyst
of example 3 (comparative) was used. Other details and results can be seen in table
3B.
Example 12
[0147] The procedure of example 11 was repeated, however using at 2. Stage conditions resulting
in higher amount of XS.
Table 3A: Polymerisation and Properties of the heterophasic polypropylene
Example |
|
Ex 8 |
Ex 8 |
Ex 9 |
|
|
1.stage |
2.stage |
2.stage |
Catalyst type |
|
Ex 2 |
Ex 2 |
Ex 2 |
Cat amount |
[mg] |
12.4 |
12.4 |
12.6 |
Bulk polymerisation |
|
|
|
|
Temperature |
[°C] |
80 |
80 |
80 |
Time |
[min] |
30 |
30 |
30 |
Gas phase polymerisation |
|
|
|
|
Hydrogen |
[mmol] |
- |
200 |
200 |
Time |
[min] |
- |
85 |
45 |
Ethylene/propylene in feed |
[mol/mol] |
- |
0.75 |
0.75 |
Ethylene fed total |
[g] |
- |
122 |
103 |
Propylene fed total |
[g] |
- |
234 |
211 |
Yield |
[g] |
251 |
465 |
439 |
Polymer product |
|
|
|
|
Ethylene in polymer |
[wt.-%] |
- |
20.4 |
17.4 |
XS |
[wt.-%] |
1.6 |
43.8 |
39.9 |
AM |
[wt.-%] |
- |
42.6 |
38.3 |
Ethylene in AM |
[wt.-%] |
- |
40.4 |
40.1 |
MFR |
[g/10min] |
13.5 |
4.1 |
5.2 |
Flow average |
[seconds] |
2.8 |
10.4 |
7.5 |
Table 3B: Polymerisation and Properties of the heterophasic polypropylene, comparative
examples
Example |
|
Ex10 |
Ex10 |
Ex 11 |
Ex 11 |
Ex 12 |
|
|
1.stage |
2.stage |
1.stage |
2.stage |
2.stage |
Catalyst type |
|
|
|
|
|
|
Cat amount |
[mg] |
11.7 |
12.7 |
16.5 |
16.5 |
16.5 |
Bulk polymerisation |
|
|
|
|
|
|
Temperature |
[°C] |
80 |
80 |
80 |
80 |
80 |
Time |
[min] |
30 |
30 |
30 |
30 |
30 |
Gas phase polymerisation |
|
|
|
|
|
|
Hydrogen |
[mmol] |
- |
180 |
- |
90 |
90 |
Time |
[min] |
- |
61 |
- |
21 |
32 |
Ethylene/propylene in feed |
[mol/mol] |
- |
0.75 |
- |
0.75 |
0.75 |
Ethylene fed total |
[g] |
- |
144 |
- |
79 |
106 |
Propylene fed total |
[g] |
- |
293 |
- |
164 |
206 |
Yield |
[g] |
274 |
606 |
299 |
436 |
519 |
Polymer product |
|
|
|
|
|
|
Ethylene in polymer |
[wt.-%] |
- |
19.1 |
- |
10.7 |
13.9 |
XS |
[wt.-%] |
1.5 |
47.8 |
1.2 |
25.6 |
34.9 |
AM |
[wt.-%] |
- |
46.2 |
- |
25 |
34 |
Ethylene in AM |
[wt.-%] |
- |
34.7 |
- |
36 |
37.1 |
MFR |
[g/10min] |
8.4 |
3.6 |
8.9 |
5.1 |
4.3 |
Flow average |
[seconds] |
2.0 |
11.6 |
1.6 |
11.4 |
too sticky |
[0148] As can be seen from the results the polymers produced with the catalyst of the invention
had a good flowability, even with a high XS values indicating a high rubber (elastomer)
amount. The results are clearly better than those produced with the comparative catalyst
3 (compact catalyst without any solid material). The results show that high ethylene
amount is not possible to incorporate into a polymer (with high XS) produced with
catalyst of example 3 without serious stickiness problems. Upper limit for XS is about
25 wt.-%. Further, results obtained with the catalyst of the invention are approximately
at the same level or even better than those obtained with a catalyst of example 4.